Settings

app/lib/settings.py

@@ -0,0 +1,110 @@
+"""All configuration via environment.
+
+Take note of the environment variable prefixes required for each
+settings class, except `AppSettings`.
+"""
+from typing import Literal, Optional, Union
+
+__all__ = [
+    "APISettings",
+    "AppSettings",
+    "DatabaseSettings",
+    "EmailSettings",
+    "OpenAPISettings",
+    "ServerSettings",
+]
+
+from pydantic import Extra
+from pydantic_settings import BaseSettings
+
+
+class BaseEnvSettings(BaseSettings):
+    class Config:
+        env_file = ".env"
+        env_file_encoding = "utf-8"
+        extra = Extra.ignore
+
+
+class AppSettings(BaseEnvSettings):
+    class Config:
+        case_sensitive = True
+
+    BUILD_NUMBER: str = "0"
+    DEBUG: bool = False
+    ENVIRONMENT: str = "local"
+    LOG_LEVEL: str = "INFO"
+    NAME: str = "addressbook"
+
+    @property
+    def slug(self) -> str:
+        return "-".join(s.lower() for s in self.NAME.split())
+
+
+class APISettings(BaseEnvSettings):
+    class Config:
+        env_prefix = "API_"
+        case_sensitive = True
+
+    CACHE_EXPIRATION: int = 60
+    DB_SESSION_DEPENDENCY_KEY: str = "db_session"
+    DEFAULT_PAGINATION_LIMIT: int = 100
+    DEFAULT_USER_NAME: str = "__default_user__"
+    HEALTH_PATH: str = "/health"
+    SECRET_KEY: str = "abc123"
+    USER_DEPENDENCY_KEY: str = "user"
+
+
+class OpenAPISettings(BaseEnvSettings):
+    class Config:
+        env_prefix = "OPENAPI_"
+        case_sensitive = True
+
+    TITLE: Optional[str] = "My Litestar App"
+    VERSION: str = "0.1.0"
+    CONTACT_NAME: str = "My Name"
+    CONTACT_EMAIL: str = "some_human@some_domain.com"
+
+
+class DatabaseSettings(BaseEnvSettings):
+    class Config:
+        env_prefix = "DB_"
+        case_sensitive = True
+
+    ECHO: bool = False
+    ECHO_POOL: Union[bool, Literal["debug"]] = False
+    POOL_DISABLE: bool = False
+    POOL_MAX_OVERFLOW: int = 10
+    POOL_SIZE: int = 5
+    POOL_TIMEOUT: int = 30
+    HOST: str = "localhost"
+    PORT: int = 5432
+    NAME: str = "db-name"
+    USER: str = "db-user"
+    PASSWORD: str = "db-password"
+
+
+class ServerSettings(BaseEnvSettings):
+    class Config:
+        env_prefix = "UVICORN_"
+        case_sensitive = True
+
+    HOST: str = "localhost"
+    LOG_LEVEL: str = "info"
+    PORT: int = 8000
+    RELOAD: bool = True
+    KEEPALIVE: int = 65
+
+
+class EmailSettings(BaseEnvSettings):
+    class Config:
+        env_prefix = "EMAIL_"
+        case_sensitive = True
+
+
+# `.parse_obj()` thing is a workaround for pyright and pydantic interplay, see:
+# https://github.com/pydantic/pydantic/issues/3753#issuecomment-1087417884
+api = APISettings.parse_obj({})
+app = AppSettings.parse_obj({})
+db = DatabaseSettings.parse_obj({})
+openapi = OpenAPISettings.parse_obj({})
+server = ServerSettings.parse_obj({})